When deploying the Exinda, though the most common topology is In Path, you can also deploy the Exinda in an Out of Path Configuration, (for instance if you have physical limitations like connection speed), though there are limitations based on how it needs to be done.
An Out of Path deployment is a topology where traffic does not need to flow through the Exinda to go from the LAN to the WAN. Traffic can flow directly from the switch to the local switch to the router and then out. However, in these cases, the Exinda is connected to the side of the main path, either in a configuration that allows for the monitoring of traffic or, more advanced still, able to perform optimization and QoS based on the core router forwarding traffic to the Exinda and the Exinda forwarding it back.
This article details three supported Out of Path topologies for Exinda.
The three supported Out of Path topologies for the Exinda are as follows:
1. The Exinda connected to a router that is configured through the Web Cache Communication Protocol (WCCP) v2.
You can read more about it here: Accelerating Traffic with WCCP
2. The Exinda connected to a router that is configured to use Policy Based Routing (PBR).
- You can read more about it here: Basic Policy-Based Routing
Note: In the topologies mentioned in points 1 and 2 above, the router will forward the information to the Exinda (based on either the configuration of the WCCPv2 or the PBR). It will examine the traffic in a way very similar to if it were In line, it will return information to the router, and the router will shape the traffic accordingly before passing it to the destination.
3. The Exinda connected to a switch that has the port connected to the Exinda configured to use SPAN / Mirroring.
- You can read more about it here: SPAN and Mirror Port Monitoring
Note: In the topology mentioned in point 3 above, the Exinda cannot perform any shaping of traffic because due to the way that Port Mirroring works, it can view the traffic, but has no logical knowledge that the traffic is being mirrored to it. In this case, reporting and monitoring will work as it does In line (with the exception of the Interfaces Graph).